1640951 has 4 divisors (see below), whose sum is σ = 1767192. Its totient is φ = 1514712.

The previous prime is 1640941. The next prime is 1640953. The reversal of 1640951 is 1590461.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1640951 - 2⁶ = 1640887 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1640951.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1640953) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 63101 + ... + 63126.

It is an arithmetic number, because the mean of its divisors is an integer number (441798).

2^1640951 is an apocalyptic number.

1640951 is a deficient number, since it is larger than the sum of its proper divisors (126241).

1640951 is a wasteful number, since it uses less digits than its factorization.

1640951 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126240.

The product of its (nonzero) digits is 1080, while the sum is 26.

The square root of 1640951 is about 1280.9960967934. The cubic root of 1640951 is about 117.9501608927.

The spelling of 1640951 in words is "one million, six hundred forty thousand, nine hundred fifty-one".